2017-11-24 10:28:31

by Zhiqiang Hou

[permalink] [raw]
Subject: [PATCH 1/2] mtd: spi-nor: add a API to restore the addressing mode

From: Hou Zhiqiang <[email protected]>

It's better to restore the addressing mode of the SPI flash
whenever remove the driver or reboot the system.

Signed-off-by: Hou Zhiqiang <[email protected]>
---
drivers/mtd/spi-nor/spi-nor.c | 8 ++++++++
include/linux/mtd/spi-nor.h | 1 +
2 files changed, 9 insertions(+)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index bc266f70a15b..801cbe99b059 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -2713,6 +2713,14 @@ static void spi_nor_resume(struct mtd_info *mtd)
dev_err(dev, "resume() failed\n");
}

+void spi_nor_restore_addr_mode(struct spi_nor *nor)
+{
+ if ((nor->addr_width == 4) &&
+ (JEDEC_MFR(nor->info) != SNOR_MFR_SPANSION) &&
+ !(nor->info->flags & SPI_NOR_4B_OPCODES))
+ set_4byte(nor, nor->info, 0);
+}
+
int spi_nor_scan(struct spi_nor *nor, const char *name,
const struct spi_nor_hwcaps *hwcaps)
{
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index d0c66a0975cf..fe9357da2049 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -398,5 +398,6 @@ struct spi_nor_hwcaps {
*/
int spi_nor_scan(struct spi_nor *nor, const char *name,
const struct spi_nor_hwcaps *hwcaps);
+void spi_nor_restore_addr_mode(struct spi_nor *nor);

#endif
--
2.14.1


From 1586045679778992165@xxx Wed Dec 06 14:37:09 +0000 2017
X-GM-THRID: 1585791835955900730
X-Gmail-Labels: Inbox,Category Forums,HistoricalUnread